The vast edge-on stretch of our home galaxy, the Milky Way, is seen intersecting the night sky above the silhouetted Rocky Mountains in this photograph. The Milky Way noticeably widens at lower right. This wider area is the central hub, or bulge, of our galaxy.

Peering into a very narrow region of the core, astronomers used the Hubble Space Telescope to study the compositions and motions of 10,000 Sun-like stars, as seen in the inset Hubble image. The analysis reveals that our galaxy's bulge is an unexpectedly dynamic environment of stars of various ages zipping around at different speeds, like travelers bustling
about a busy airport. The study yields important new clues to the complexity of the central bulge and our Milky Way's evolution over billions of years.

The Hubble image is a composite of exposures taken in near-infrared and visible light with Hubble's Wide Field Camera 3. The observations are part of two Hubble surveys: the Galactic Bulge Treasury Program and the Sagittarius Window Eclipsing Extrasolar Planet Search.